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Water and Pathogenic Viruses Inactivation—Food Engineering Perspectives النص الكامل
2020
Roos, Yrjö H.
Water is an essential component of food structures and biological materials. The importance of water as a parameter affecting virion stability and inactivation has been recognized across disciplinary areas. The large number of virus species, differences in spreading, likelihood of foodborne infections, unknown infective doses, and difficulties of infective virus quantification are often limiting experimental approaches to establish accurate data required for detailed understanding of virions’ stability and inactivation kinetics in various foods. Furthermore, non-foodborne viruses, as shown by the SARS-CoV-2 (Covid-19) pandemic, may spread within the food chain. Traditional food engineering benefits from kinetic data on effects of relative humidity (RH) and temperature on virion inactivation. The stability of enteric viruses, human norovirus (HuNoV), and hepatitis A (HAV) virions in food materials and their resistance against inactivation in traditional food processing and preservation is well recognized. It appears that temperature-dependence of virus inactivation is less affected by virus strains than differences in temperature and RH sensitivity of individual virus species. Pathogenic viruses are stable at low temperatures typical of food storage conditions. A significant change in activation energy above typical protein denaturation temperatures suggests a rapid inactivation of virions. Furthermore, virus inactivation mechanisms seem to vary according to temperature. Although little is known on the effects of water on virions’ resistance during food processing and storage, dehydration, low RH conditions, and freezing stabilize virions. Enveloped virions tend to have a high stability at low RH, but low temperature and high RH may also stabilize such virions on metal and other surfaces for several days. Food engineering has contributed to significant developments in stabilization of nutrients, flavors, and sensitive components in food materials which provides a knowledge base for development of technologies to inactivate virions in foods and environment. Novel food processing, particularly high pressure processing (HPP) and cold plasma technologies, seem to provide efficient means for virion inactivation and food quality retention prior to packaging or food preservation by traditional technologies.
اظهر المزيد [+] اقل [-]Effects of novel colour and smell on the response of naive chicks towards food and water
1996
Marples, N.M. | Roper, T.J.
Many warningly coloured prey emit a conspicuous smell of pyrazines when attacked by a predator and it has been suggested that this odour cue constitutes part of the prey's aposematic anti-predator defences. The aim of the study was to test the hypothesis that pyrazine odours enhance the neophobic response of birds towards prey that is novel in appearance. Naive domestic chicks, Gallus gallus domesticus, were presented with food or water that was either familiar or novel (coloured with food dye) in appearance, in the presence or absence of five different odours. The odours in question were 2-methoxy-3-sec-butyl pyrazine, 2-methoxy-3-isobutyl pyrazine, almond oil, vanilla oil and thiazole. Presence of each of the pyrazines and of almond odour increased the latency with which chicks ate or drank, but only when the food or water was a novel colour. The effect was weaker with vanilla odour and absent with thiazole. When odours of 2-methoxy-3-sec-butyl pyrazine and thiazole were paired with a novel-coloured environment, eating and drinking were not inhibited. This suggests that odours naturally associated with chemical defence in insects or plants do enhance neophobia, but only when presented in conjunction with prey that has a novel appearance. However, confounding factors such as differences in odour intensity cannot at present be excluded. The implications of the results for theories concerning the evolution of warning coloration are discussed.
اظهر المزيد [+] اقل [-]Water-based oligochitosan and nanowhisker chitosan as potential food preservatives for shelf-life extension of minced pork النص الكامل
2014
Chantarasataporn, Patomporn | Tepkasikul, Preenapha | Kingcha, Yutthana | Yoksan, Rangrong | Pichyangkura, Rath | Visessanguan, Wonnop | Chirachanchai, Suwabun
Water-based chitosans in the forms of oligochitosan (OligoCS) and nanowhisker chitosan (CSWK) are proposed as a novel food preservative based on a minced pork model study. The high surface area with a positive charge over the neutral pH range (pH 5–8) of OligoCS and CSWK lead to an inhibition against Gram-positive (Staphylococcusaureus, Listeriamonocytogenes, and Bacilluscereus) and Gram-negative microbes (Salmonellaenteritidis and Escherichiacoli O157:H7). In the minced pork model, OligoCS effectively performs a food preservative for shelf-life extension as clarified from the retardation of microbial growth, biogenic amine formation and lipid oxidation during the storage. OligoCS maintains almost all myosin heavy chain protein degradation as observed in the electrophoresis. The present work points out that water-based chitosan with its unique morphology not only significantly inhibits antimicrobial activity but also maintains the meat quality with an extension of shelf-life, and thus has the potential to be used as a food preservative.
اظهر المزيد [+] اقل [-]Safety of water extract of Cistanche tubulosa stems as a Novel food pursuant to Regulation (EU) 2015/2283 النص الكامل
2021
EFSA NDA Panel (EFSA Panel on Nutrition, Novel Foods and Food Allergens) | Dominique Turck | Jacqueline Castenmiller | Stefaan De Henauw | Karen Ildico Hirsch‐Ernst | John Kearney | Alexandre Maciuk | Inge Mangelsdorf | Harry J McArdle | Androniki Naska | Carmen Pelaez | Kristina Pentieva | Alfonso Siani | Frank Thies | Sophia Tsabouri | Marco Vinceti | Francesco Cubadda | Thomas Frenzel | Marina Heinonen | Rosangela Marchelli | Monika Neuhäuser‐Berthold | Morten Poulsen | Miguel Prieto Maradona | Josef Rudolf Schlatter | Henk van Loveren | Wolfgang Gelbmann | Helle Katrine Knutsen
Abstract Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on water extract of Cistanche tubulosa stems as a novel food (NF) for its use in food supplements (FS) and foods for special medical purposes (FSMP). The target population is the general adult population excluding pregnant and lactating women. The applicant proposes a maximum daily intake of 2 g for FS and a maximum use level of 10% in FSMP. The characteristic components of the extract are phenylethanoid glycosides (at least 70% of the NF), in particular, echinacoside (25–45% of the NF). The NF has been authorised as a prescription drug in China in 2005 for the treatment of vascular dementia. The Panel notes that an integrated analysis of three studies covering 1,076 patients with vascular dementia treated with the proposed NF at a daily dose of 1,800 mg, reported that 12 adverse events (AEs) were classified to be ‘definitely’, ‘probably’ or ‘possibly related’ to the exposure to the NF. Two of these AE were classified as severe (cerebral haemorrhage and epilepsy). The Panel considers that the reported AEs raise safety concerns. The Panel also notes the limitations of the provided toxicological studies, in particular the non‐compliance with the EFSA approach on the genotoxicity testing strategy and the non‐compliance with good laboratory practice (GLP) and the respective OECD Guidance documents of the repeated dose toxicity studies. In view of the AEs in the human studies, the Panel considers that additional toxicological studies, following testing guidelines would not be able to overcome the concerns raised from the human studies. The Panel concludes that the safety of the NF has not been established.
اظهر المزيد [+] اقل [-]Safety of water lentil protein concentrate from a mixture of Lemna gibba and Lemna minor as a novel food pursuant to Regulation (EU) 2015/2283 النص الكامل
2023
EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) | Dominique Turck | Torsten Bohn | Jacqueline Castenmiller | Stefaan De Henauw | Karen Ildico Hirsch‐Ernst | Alexandre Maciuk | Inge Mangelsdorf | Harry J McArdle | Androniki Naska | Carmen Pelaez | Kristina Pentieva | Alfonso Siani | Frank Thies | Sophia Tsabouri | Marco Vinceti | Margarita Aguilera‐Gómez | Francesco Cubadda | Thomas Frenzel | Marina Heinonen | Miguel Prieto Maradona | Rosangela Marchelli | Monika Neuhäuser‐Berthold | Morten Poulsen | Josef Rudolf Schlatter | Henk vanLoveren | Eirini Kouloura | Helle Katrine Knutsen
Abstract Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on water lentil protein concentrate from a mixture of Lemna gibba and Lemna minor as a novel food (NF) pursuant to Regulation (EU) 2015/2283. Water lentil protein concentrate is produced from two water lentil species (L. gibba and L. minor) by separation of the protein fraction of the plant material from fibres, followed by pasteurisation and spray drying. The NF consists mainly of protein, fibre, fat and ash. The applicant proposed to use the NF as a food ingredient in a variety of food categories and as a food supplement. The target population is the general population when used as a food ingredient and exclusively adults when used as a food supplement. The Panel considers that taking into account the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. There are no concerns regarding genotoxicity of the NF. The Panel considers that the risk of the NF triggering allergic reactions is low. The Panel concludes that the NF, water lentil protein concentrate from a mixture of L. gibba and L. minor, is safe under the proposed conditions of use.
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